191 research outputs found
903-8 Mitogenic Effect of Thromboxane A2and Its Synergistic Interaction with Serotonin on Smooth Muscle Cell Proliferation is Reversed by Ridogrel
BackgroundThromboxane A2(TxA2) and serotonin (5HT) released from aggregating platelets are known mitogens for vascular smooth muscle cells (SMC). Recently we reported that TxA2and 5HT act synergistically in inducing proliferation of SMC and may contribute to the development of restenosis following vascular injury.PurposeIn this study, we examined whether ridogrel (a TxA2synthase inhibitor/receptor antagonist) can inhibit the TxA2induced SMC proliferation both in the presence and absence of 5HT.MethodsCanine aortic primary SMC were preincubated with either 30 μg/ml of Ridogrel in phosphate buffered saline (PBS) or equal volume of PBS, as control, for 2 hrs in serum free medium. Increasing concentrations of U46619 (a TxA2mimetic) with or without 5HT were then added and 3H-thymidine incorporated into DNA of the SMC was measured.ResultsControl (PBS) 5HT Concentration(μM)Rido9rel 30 μg/ml 5HT Concentration(μM)05500550TxA20 nM100236±37222±568±4306±3212±13TxA27.5 nM100±1394±201131±9784±8294±27*249±6*TxA275 nmM173±29541±691369±14674±117*283±24*279±17*TxA2750 nM282±8795±221569±10376±27*285±28*274±21*Values are % of control: Control=100% =9023±621 cpm/106cells. n =3*p<0.001 compared to corresponding PBS treated controlsThe data show that unlike the PBS treated controls, ridogrel reversed both the mitogenic effect of TxA2on SMC as well as its synergistic interaction with 5HT in inducing cellular proliferation.ConclusionThe data indicate the specificity of the interaction of TxA2with 5HT in inducing SMC proliferation. This suggests a potential role forthe combined use of TxA2synthase inhibitor/receptor antagonist and 5HT receptor antagonist for inhibiting SMC proliferation at sites of vascular injury
Quantitative Assessment of Program Outcomes Using Longitudinal Data from the FE Exam
There have been many studies providing details on using results from the Fundamentals of Engineering (FE) exam as metrics for meeting ABET program outcomes1. However, implementing an FE-based set of metrics poses challenges not limited to assessing validity of results. Programs using FE-based metrics must also determine the position of the metrics in the overall assessment process. We present a method for using FE-based metrics as an integral part of the ABET program assessment process. The principle issues we address are: (1) The validity of using FE metrics for a group of graduating students when not all of them take the exam; (2) Establishing and quantifying levels of performance; and (3) Creating a trigger mechanism for taking action based upon longitudinal results.
The Department of Mechanical and Biomedical Engineering at Boise State University created a process which integrates metrics from the FE results with other metrics in our loop for outcomes assessment and continuous improvement. Our process prevents us from taking inappropriate action based upon isolated negative results from the FE exam. We have used our process to make a demonstrable improvement in our curriculum. Two examples of faculty action taken due to unsatisfactory and questionable results from the FE metric before our last ABET visit are presented and discussed
Induction of spermidine/spermine N1-acetyltransferase activity in Chinese-hamster ovary cells by N1N11-bis(ethyl)norspermine (corrected) and related compounds
Worldwide prevalence, genotype distribution and management of hepatitis C
epatitis C virus (HCV) is one of the leading causes of chronic liver disease, cirrhosis, and hepatocellular carcinoma, resulting in major global public health concerns. The HCV infection is unevenly distributed worldwide, with variations in prevalence across and within countries. The studies on molecular epidemiology conducted in several countries provide an essential supplement for a comprehensive knowledge of HCV epidemiology, genotypes, and subtypes, along with providing information on the impact of current and earlier migratory flows. HCV is phylogenetically classified into 8 major genotypes and 57 subtypes. HCV genotype and subtype distribution differ according to geographic origin and transmission risk category. Unless people with HCV infection are detected and treated appropriately, the number of deaths due to the disease will continue to increase. In 2015, 1.75 million new viral infections were mostly due to unsafe healthcare procedures and drug use injections. In the same year, access to direct-acting antivirals was challenging and varied in developing and developed countries, affecting HCV cure rates based on their availability. The World Health Assembly, in 2016, approved a global strategy to achieve the elimination of the HCV public health threat by 2030 (by reducing new infections by 90% and deaths by 65%). Globally, countries are implementing policies and measures to eliminate HCV risk based on their distribution of genotypes and prevalence
The islet-resident macrophage is in an inflammatory state and senses microbial products in blood
Bidirectional autoregulatory mechanism of metastasis-associated protein 1-alternative reading frame pathway in oncogenesis
Although metastasis-associated protein 1 (MTA1), a component of the nucleosome remodeling and histone deacetylation complex, is widely up-regulated in human cancers and correlates with tumor metastasis, its regulatory mechanism and related signaling pathways remain unknown. Here, we report a previously unrecognized bidirectional autoregulatory loop between MTA1 and tumor suppressor alternative reading frame (ARF). MTA1 transactivates ARF transcription by recruiting the transcription factor c-Jun onto the ARF promoter in a p53-independent manner. ARF, in turn, negatively regulates MTA1 expression independently of p53 and c-Myc. In this context, ARF interacts with transcription factor specificity protein 1 (SP1) and promotes its proteasomal degradation by enhancing its interaction with proteasome subunit regulatory particle ATPase 6, thereby abrogating the ability of SP1 to stimulate MTA1 transcription. ARF also physically associates with MTA1 and affects its protein stability. Thus, MTA1-mediated activation of ARF and ARF-mediated functional inhibition of MTA1 represent a p53-independent bidirectional autoregulatory mechanism in which these two opposites act in concert to regulate cell homeostasis and oncogenesis, depending on the cellular context and the environment
Induction of aromatic ring: cleavage dioxygenases in Stenotrophomonas maltophilia strain KB2 in cometabolic systems
Stenotrophomonas maltophilia KB2 is known to produce different enzymes of dioxygenase family. The aim of our studies was to determine activity of these enzymes after induction by benzoic acids in cometabolic systems with nitrophenols. We have shown that under cometabolic conditions KB2 strain degraded 0.25–0.4 mM of nitrophenols after 14 days of incubation. Simultaneously degradation of 3 mM of growth substrate during 1–3 days was observed depending on substrate as well as cometabolite used. From cometabolic systems with nitrophenols as cometabolites and 3,4-dihydroxybenzoate as a growth substrate, dioxygenases with the highest activity of protocatechuate 3,4-dioxygenase were isolated. Activity of catechol 1,2- dioxygenase and protocatechuate 4,5-dioxygenase was not observed. Catechol 2,3-dioxygenase was active only in cultures with 4-nitrophenol. Ability of KB2 strain to induce and synthesize various dioxygenases depending on substrate present in medium makes this strain useful in bioremediation of sites contaminated with different aromatic compounds
HVEM Signalling Promotes Colitis
Background
Tumor necrosis factor super family (TNFSF) members regulate important processes involved in cell proliferation, survival and differentiation and are therefore crucial for the balance between homeostasis and inflammatory responses. Several members of the TNFSF are closely associated with inflammatory bowel disease (IBD). Thus, they represent interesting new targets for therapeutic treatment of IBD.
Methodology/Principal Findings
We have used mice deficient in TNFSF member HVEM in experimental models of IBD to investigate its role in the disease process. Two models of IBD were employed: i) chemical-induced colitis primarily mediated by innate immune cells; and ii) colitis initiated by CD4+CD45RBhigh T cells following their transfer into immuno-deficient RAG1-/- hosts. In both models of disease the absence of HVEM resulted in a significant reduction in colitis and inflammatory cytokine production.
Conclusions
These data show that HVEM stimulatory signals promote experimental colitis driven by innate or adaptive immune cells
Multi-ancestry meta-analysis of tobacco use disorder prioritizes novel candidate risk genes and reveals associations with numerous health outcomes
Tobacco use disorder (TUD) is the most prevalent substance use disorder in the world. Genetic factors influence smoking behaviors, and although strides have been made using genome-wide association studies (GWAS) to identify risk variants, the majority of variants identified have been for nicotine consumption, rather than TUD. We leveraged five biobanks to perform a multi-ancestral meta-analysis of TUD (derived via electronic health records, EHR) in 898,680 individuals (739,895 European, 114,420 African American, 44,365 Latin American). We identified 88 independent risk loci; integration with functional genomic tools uncovered 461 potential risk genes, primarily expressed in the brain. TUD was genetically correlated with smoking and psychiatric traits from traditionally ascertained cohorts, externalizing behaviors in children, and hundreds of medical outcomes, including HIV infection, heart disease, and pain. This work furthers our biological understanding of TUD and establishes EHR as a source of phenotypic information for studying the genetics of TUD
Mineralization of Acephate, a Recalcitrant Organophosphate Insecticide Is Initiated by a Pseudomonad in Environmental Samples
An aerobic bacterium capable of breaking down the pesticide acephate (O,S-dimethyl acetyl phosphoramidothioic acid) was isolated from activated sludge collected from a pesticide manufacturing facility. A phylogenetic tree based on the 16 S rRNA gene sequence determined that the isolate lies within the Pseudomonads. The isolate was able to grow in the presence of acephate at concentrations up to 80 mM, with maximum growth at 40 mM. HPLC and LC-MS/MS analysis of spent medium from growth experiments and a resting cell assay detected the accumulation of methamidophos and acetate, suggesting initial hydrolysis of the amide linkage found between these two moieties. As expected, the rapid decline in acephate was coincident with the accumulation of methamidophos. Methamidophos concentrations were maintained over a period of days, without evidence of further metabolism or cell growth by the cultures. Considering this limitation, strains such as described in this work can promote the first step of acephate mineralization in soil microbial communities
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